| //! A module for searching for libraries |
| |
| use rustc_fs_util::try_canonicalize; |
| use smallvec::{smallvec, SmallVec}; |
| use std::env; |
| use std::fs; |
| use std::path::{Path, PathBuf}; |
| |
| use crate::search_paths::{PathKind, SearchPath}; |
| use rustc_fs_util::fix_windows_verbatim_for_gcc; |
| |
| #[derive(Clone)] |
| pub struct FileSearch<'a> { |
| sysroot: &'a Path, |
| triple: &'a str, |
| search_paths: &'a [SearchPath], |
| tlib_path: &'a SearchPath, |
| kind: PathKind, |
| } |
| |
| impl<'a> FileSearch<'a> { |
| pub fn search_paths(&self) -> impl Iterator<Item = &'a SearchPath> { |
| let kind = self.kind; |
| self.search_paths |
| .iter() |
| .filter(move |sp| sp.kind.matches(kind)) |
| .chain(std::iter::once(self.tlib_path)) |
| } |
| |
| pub fn get_lib_path(&self) -> PathBuf { |
| make_target_lib_path(self.sysroot, self.triple) |
| } |
| |
| pub fn get_self_contained_lib_path(&self) -> PathBuf { |
| self.get_lib_path().join("self-contained") |
| } |
| |
| pub fn new( |
| sysroot: &'a Path, |
| triple: &'a str, |
| search_paths: &'a [SearchPath], |
| tlib_path: &'a SearchPath, |
| kind: PathKind, |
| ) -> FileSearch<'a> { |
| debug!("using sysroot = {}, triple = {}", sysroot.display(), triple); |
| FileSearch { sysroot, triple, search_paths, tlib_path, kind } |
| } |
| |
| /// Returns just the directories within the search paths. |
| pub fn search_path_dirs(&self) -> Vec<PathBuf> { |
| self.search_paths().map(|sp| sp.dir.to_path_buf()).collect() |
| } |
| } |
| |
| pub fn make_target_lib_path(sysroot: &Path, target_triple: &str) -> PathBuf { |
| let rustlib_path = rustc_target::target_rustlib_path(sysroot, target_triple); |
| PathBuf::from_iter([sysroot, Path::new(&rustlib_path), Path::new("lib")]) |
| } |
| |
| #[cfg(unix)] |
| fn current_dll_path() -> Result<PathBuf, String> { |
| use std::ffi::{CStr, OsStr}; |
| use std::os::unix::prelude::*; |
| |
| #[cfg(not(target_os = "aix"))] |
| unsafe { |
| let addr = current_dll_path as usize as *mut _; |
| let mut info = std::mem::zeroed(); |
| if libc::dladdr(addr, &mut info) == 0 { |
| return Err("dladdr failed".into()); |
| } |
| if info.dli_fname.is_null() { |
| return Err("dladdr returned null pointer".into()); |
| } |
| let bytes = CStr::from_ptr(info.dli_fname).to_bytes(); |
| let os = OsStr::from_bytes(bytes); |
| Ok(PathBuf::from(os)) |
| } |
| |
| #[cfg(target_os = "aix")] |
| unsafe { |
| // On AIX, the symbol `current_dll_path` references a function descriptor. |
| // A function descriptor is consisted of (See https://reviews.llvm.org/D62532) |
| // * The address of the entry point of the function. |
| // * The TOC base address for the function. |
| // * The environment pointer. |
| // The function descriptor is in the data section. |
| let addr = current_dll_path as u64; |
| let mut buffer = vec![std::mem::zeroed::<libc::ld_info>(); 64]; |
| loop { |
| if libc::loadquery( |
| libc::L_GETINFO, |
| buffer.as_mut_ptr() as *mut i8, |
| (std::mem::size_of::<libc::ld_info>() * buffer.len()) as u32, |
| ) >= 0 |
| { |
| break; |
| } else { |
| if std::io::Error::last_os_error().raw_os_error().unwrap() != libc::ENOMEM { |
| return Err("loadquery failed".into()); |
| } |
| buffer.resize(buffer.len() * 2, std::mem::zeroed::<libc::ld_info>()); |
| } |
| } |
| let mut current = buffer.as_mut_ptr() as *mut libc::ld_info; |
| loop { |
| let data_base = (*current).ldinfo_dataorg as u64; |
| let data_end = data_base + (*current).ldinfo_datasize; |
| if (data_base..data_end).contains(&addr) { |
| let bytes = CStr::from_ptr(&(*current).ldinfo_filename[0]).to_bytes(); |
| let os = OsStr::from_bytes(bytes); |
| return Ok(PathBuf::from(os)); |
| } |
| if (*current).ldinfo_next == 0 { |
| break; |
| } |
| current = |
| (current as *mut i8).offset((*current).ldinfo_next as isize) as *mut libc::ld_info; |
| } |
| return Err(format!("current dll's address {} is not in the load map", addr)); |
| } |
| } |
| |
| #[cfg(windows)] |
| fn current_dll_path() -> Result<PathBuf, String> { |
| use std::ffi::OsString; |
| use std::io; |
| use std::os::windows::prelude::*; |
| |
| use windows::{ |
| core::PCWSTR, |
| Win32::Foundation::HMODULE, |
| Win32::System::LibraryLoader::{ |
| GetModuleFileNameW, GetModuleHandleExW, GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS, |
| }, |
| }; |
| |
| let mut module = HMODULE::default(); |
| unsafe { |
| GetModuleHandleExW( |
| GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS, |
| PCWSTR(current_dll_path as *mut u16), |
| &mut module, |
| ) |
| } |
| .map_err(|e| e.to_string())?; |
| |
| let mut filename = vec![0; 1024]; |
| let n = unsafe { GetModuleFileNameW(module, &mut filename) } as usize; |
| if n == 0 { |
| return Err(format!("GetModuleFileNameW failed: {}", io::Error::last_os_error())); |
| } |
| if n >= filename.capacity() { |
| return Err(format!("our buffer was too small? {}", io::Error::last_os_error())); |
| } |
| |
| filename.truncate(n); |
| |
| Ok(OsString::from_wide(&filename).into()) |
| } |
| |
| pub fn sysroot_candidates() -> SmallVec<[PathBuf; 2]> { |
| let target = crate::config::host_triple(); |
| let mut sysroot_candidates: SmallVec<[PathBuf; 2]> = |
| smallvec![get_or_default_sysroot().expect("Failed finding sysroot")]; |
| let path = current_dll_path().and_then(|s| try_canonicalize(s).map_err(|e| e.to_string())); |
| if let Ok(dll) = path { |
| // use `parent` twice to chop off the file name and then also the |
| // directory containing the dll which should be either `lib` or `bin`. |
| if let Some(path) = dll.parent().and_then(|p| p.parent()) { |
| // The original `path` pointed at the `rustc_driver` crate's dll. |
| // Now that dll should only be in one of two locations. The first is |
| // in the compiler's libdir, for example `$sysroot/lib/*.dll`. The |
| // other is the target's libdir, for example |
| // `$sysroot/lib/rustlib/$target/lib/*.dll`. |
| // |
| // We don't know which, so let's assume that if our `path` above |
| // ends in `$target` we *could* be in the target libdir, and always |
| // assume that we may be in the main libdir. |
| sysroot_candidates.push(path.to_owned()); |
| |
| if path.ends_with(target) { |
| sysroot_candidates.extend( |
| path.parent() // chop off `$target` |
| .and_then(|p| p.parent()) // chop off `rustlib` |
| .and_then(|p| p.parent()) // chop off `lib` |
| .map(|s| s.to_owned()), |
| ); |
| } |
| } |
| } |
| |
| return sysroot_candidates; |
| } |
| |
| /// Returns the provided sysroot or calls [`get_or_default_sysroot`] if it's none. |
| /// Panics if [`get_or_default_sysroot`] returns an error. |
| pub fn materialize_sysroot(maybe_sysroot: Option<PathBuf>) -> PathBuf { |
| maybe_sysroot.unwrap_or_else(|| get_or_default_sysroot().expect("Failed finding sysroot")) |
| } |
| |
| /// This function checks if sysroot is found using env::args().next(), and if it |
| /// is not found, finds sysroot from current rustc_driver dll. |
| pub fn get_or_default_sysroot() -> Result<PathBuf, String> { |
| // Follow symlinks. If the resolved path is relative, make it absolute. |
| fn canonicalize(path: PathBuf) -> PathBuf { |
| let path = try_canonicalize(&path).unwrap_or(path); |
| // See comments on this target function, but the gist is that |
| // gcc chokes on verbatim paths which fs::canonicalize generates |
| // so we try to avoid those kinds of paths. |
| fix_windows_verbatim_for_gcc(&path) |
| } |
| |
| fn default_from_rustc_driver_dll() -> Result<PathBuf, String> { |
| let dll = current_dll_path().map(|s| canonicalize(s))?; |
| |
| // `dll` will be in one of the following two: |
| // - compiler's libdir: $sysroot/lib/*.dll |
| // - target's libdir: $sysroot/lib/rustlib/$target/lib/*.dll |
| // |
| // use `parent` twice to chop off the file name and then also the |
| // directory containing the dll |
| let dir = dll.parent().and_then(|p| p.parent()).ok_or(format!( |
| "Could not move 2 levels upper using `parent()` on {}", |
| dll.display() |
| ))?; |
| |
| // if `dir` points target's dir, move up to the sysroot |
| let mut sysroot_dir = if dir.ends_with(crate::config::host_triple()) { |
| dir.parent() // chop off `$target` |
| .and_then(|p| p.parent()) // chop off `rustlib` |
| .and_then(|p| p.parent()) // chop off `lib` |
| .map(|s| s.to_owned()) |
| .ok_or_else(|| { |
| format!("Could not move 3 levels upper using `parent()` on {}", dir.display()) |
| })? |
| } else { |
| dir.to_owned() |
| }; |
| |
| // On multiarch linux systems, there will be multiarch directory named |
| // with the architecture(e.g `x86_64-linux-gnu`) under the `lib` directory. |
| // Which cause us to mistakenly end up in the lib directory instead of the sysroot directory. |
| if sysroot_dir.ends_with("lib") { |
| sysroot_dir = |
| sysroot_dir.parent().map(|real_sysroot| real_sysroot.to_owned()).ok_or_else( |
| || format!("Could not move to parent path of {}", sysroot_dir.display()), |
| )? |
| } |
| |
| Ok(sysroot_dir) |
| } |
| |
| // Use env::args().next() to get the path of the executable without |
| // following symlinks/canonicalizing any component. This makes the rustc |
| // binary able to locate Rust libraries in systems using content-addressable |
| // storage (CAS). |
| fn from_env_args_next() -> Option<PathBuf> { |
| match env::args_os().next() { |
| Some(first_arg) => { |
| let mut p = PathBuf::from(first_arg); |
| |
| // Check if sysroot is found using env::args().next() only if the rustc in argv[0] |
| // is a symlink (see #79253). We might want to change/remove it to conform with |
| // https://www.gnu.org/prep/standards/standards.html#Finding-Program-Files in the |
| // future. |
| if fs::read_link(&p).is_err() { |
| // Path is not a symbolic link or does not exist. |
| return None; |
| } |
| |
| // Pop off `bin/rustc`, obtaining the suspected sysroot. |
| p.pop(); |
| p.pop(); |
| // Look for the target rustlib directory in the suspected sysroot. |
| let mut rustlib_path = rustc_target::target_rustlib_path(&p, "dummy"); |
| rustlib_path.pop(); // pop off the dummy target. |
| rustlib_path.exists().then_some(p) |
| } |
| None => None, |
| } |
| } |
| |
| Ok(from_env_args_next().unwrap_or(default_from_rustc_driver_dll()?)) |
| } |
